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Faran uses the maximum alpha value in order to avoid underestimation which is ~ 62.98 km/ms in our case. Also Faran calculates alpha based on PingER historical data to all the world regions and in this study we only used the North American PingER sites. Looking at the frequency histogram of alpha for the SLAC landmark to Norther North American target sites it is seen that this is a reasonable maximum value.
Europe
Conclusion
References
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